1. Field of the Invention
The present invention relates to a method for producing a plastic molding including a core which is provided on an outer surface thereof with a foam with a skin, and a molding die apparatus for producing the same. Note that the "outer surface of the core" refers to the surface of the core that is located adjacent to an outer surface of a plastic molding (product) to be obtained.
2. Description of the Related Art
For instance, a conventional instrument panel for an automobile is usually made of a core (or base or substrate) which is provided on the outer surface thereof with a pad comprising a foam with a skin.
In a known method for producing such a plastic molding (product) having on the outer surface thereof a foam with a skin, an outer skin 112 which is provided, on a periphery of a product portion 110 thereof, with a skirt 111 is disposed on a lower die 115 so that the skirt 111 is located on a parting of a die assembly which surrounds a cavity 114 of a die assembly 113 defined by the lower die 115 and an upper die 116, as can be seen in FIG. 14. The core 118 is disposed on the die surface 117 of the upper die 116. When the upper die 116 and the lower die 115 are closed, the skirt 111 is held between and by the upper and lower dies. In this state, a foaming material poured in the cavity between the core 118 and a product portion 110 of the skin is foamed to be integral with the core and the skin. Finally, the skirt 111 is cut at the periphery thereof and removed from the plastic molding thus produced. Note that the lower die 115 in FIG. 14 is provided with split dies 119 which constitute parts thereof, for an ease of removal of the molding (product) from the die assembly. The split dies (parts of lower die) are provided with projections 120 provided on the parting, so that the projections 120 can be fitted in corresponding recesses 121 formed on the outer end 112 extending from the skirt 111.
The skirt 111 is adapted to seal the connection between the upper and lower dies during the foaming operation. The skirt 111 which is unnecessary in a product must be finally cut and removed as mentioned above. Consequently, not only is there a waste of material of which the skin is made, but also a troublesome trimming operation to cut and remove the skirt is necessary in the prior art, as mentioned above.